Append data.id to existing locals block - Applying Azurerm policies to AKS

I would like to apply multiple Azure Policies to AKS. It seems to be complex to achieve in loop e.g.

locals {
  policylist = [
    { name = "Do not allow privileged containers in Kubernetes cluster", foldername = "folder0" },
    { name = "Enforce HTTPS ingress in Kubernetes cluster", foldername = "folder1" },
     ]
data "azurerm_policy_definition" "example" {
  count = "${length(local.policylist)}"
  display_name = "${local.policylist[count.index].name}"

}

resource "azurerm_policy_assignment" "example" {
    count                = "${length(local.policylist)}"
    name                 = data.azurerm_policy_definition.example[count.index].name
    policy_definition_id = data.azurerm_policy_definition.example.id
    parameters           = file("${path.module}/policyjson/${local.policylist[count.index].fname}/params.json")
    scope                = azurerm_resource_group.example.id
}

This logic may create more issue since count index would be different in local.policylist and data.azurerm_policy_definition

How can I append ID values back to local.policylist only after matching correct name?

e.g. 
policylist = [
  {name = "", foldername="", id=""}
]